Jam proof door clutch

ABSTRACT

A vertically extending leaf is pivotally mounted on the end of a hoistway door operating clutch vane and spring biased to lie in the plane of the operating face of the vane. The spring exerts a force on the leaf sufficiently strong to unlock the unlocking roller of a conventional hoistway door operating mechanism, but will yield to allow the leaf to pivot when it engages only the locked opening roller, thereby permitting the clutch mechanism to pass and the car door to open when the car is misaligned to the extent that the unlocking roller is not engaged.

United States Patent [191 Atkey JAM PROOF DOOR CLUTCH [75] Inventor: Richard E. Atkey, Memphis, Tenn.

[73] Assignee: Dover Corporation, Memphis, Tenn.

[22] Filed: July 12, 1971 [21] Appl. No.: 161,663

3,638,762 2/1972 Johns 187/52 FOREIGN PATENTS OR APPLICATIONS 962,422 7/1964 Great Britain 187/52 June 12, 1973 Primary ExaminerEvon C. Blunk Assistant ExaminerMerle F. Maffei Attorney-Granville M. Brumbaugh et al.

[57] ABSTRACT A vertically extending leaf is pivotally mounted on the end of a hoistway door operating clutch vane and spring biased to lie in the plane of the operating face of the vane. The spring exerts a force on the leaf sufficiently strong to unlock the unlocking roller of a conventional hoistway door operating mechanism, but will yield to allow the leaf to pivot when it engages only the locked opening roller, thereby permitting the clutch mechanism to pass and the car door to open when the car is misaligned to the extent that the unlocking roller is not engaged.

9 Claims, 9 Drawing Figures PATENIED 1 2 I975 3. 738 ,454

sum 1 or 3 HOISTWAY INVENTOR. DO OR RICHARD E. ATKEY ATTORNEYS PATENTEU 3, 738.454

SHEET 2 or a PRIOR ART INVENTOR. RICHARD E. ATKEY A TTOR/VEYS Pmcmww m 3,738,454

SHEET 30F 3 OOOOOOOO I/VVE/VTOR RICHARD E. ATKEY GMIGAMIDWQQ*W his ATTORNEYS JAM PROOF DOOR CLUTCH This invention relates to a mechanism for operating sliding doors, and, more particularly, to a novel and improved clutch mechanism for opening a hoistway door by means of an elevator car door.

In a modern high speed elevators, it is common practice to operate the elevator car door by means of an electric motor carried on the roof of the car and connected to the car door by means of a suitable linkage. It is also the usual practice to operate the hoistway doors by means of an interengaging clutch mechanism carried by the car door. It is thus possible to use a single motor to operate both the car and hoistway doors, thereby achieving simplicity and efficiency in the elevator mechanism as well as assuring simultaneous opening and closing of the car and hoistway doors.

A clutch mechanism in very wide use throughout the elevator industry for this purpose includes a pair of parallel, vertically extending, horizontally spaced clutch vanes carried by the elevator car door used in conjunction with a pair of vertically spaced rollers carried by the hoistway door. The rollers are positioned on each hoistway door such that the parallel clutch vanes bracket the pair of rollers when the elevator car door is aligned opposite the hoistway door at each floor. Opening movement of the car door then carries the opening vane of the clutch mechanism into engagement with the pair of rollers on the hoistway door so that the hoistway door opens simultaneously with the car door. Closing movement of the elevator car door causes the closing vane to engage the rollers and both doors close simultaneously.

It is necessary to provide an automatic locking mechanism for the hoistway door to prevent its opening until the elevator car is aligned with the hoistway entrance. This automatic locking and unlocking of the hoistway door is achieved by means of one of the two rollers connected to the hoistway door. This roller, hereinafter referred to as the unlocking roller is journaled in one arm of a bell crank, the other arm of which is connected to the hoistway door lock. When the unlocking roller on the end of the roller arm of the bell crank is vertically misaligned with the other of the two rollers, hereinafter referred to as the operating roller, the locking arm of the bell crank will lock the hoistway door; when the two rollers are vertically aligned, the locking arm of the bell crank will be pivoted to unlock the hoistway door.

To open the hoistway door, the opening vane first engages the unlocking roller and pushes it into vertical alignment with the operating roller. This pivots the locking arm nd disengages the lock to thereby unlock the hoistway door. The opening vane continues its horizontal movement, pushing now against the aligned unlocking roller and operating roller, to open the hoistway door to which the operating roller is attached.

A problem, however, has been encountered in elevators using this type of mechanism. It has been noted that on infrequent occasions the elevator car will stop and the door operating motor will be energized, but the car door will not open. When this happens, the elevator car must be restarted and allowed to travel a few more inches before the car and hoistway doors will open. This occurrence is disconcerting and annoying to the passengers and, of course, is detrimental to the public confidence in the company that makes the elevator.

Applicant has discovered the cause of this occasional mysterious failure of the car door to open. When the car stops in the hoistway at a position misaligned with the hoistway door such that the opening vane is horizontally aligned with the operating roller but not the unlocking roller, the vane will engage only the operating roller. Since the unlocking roller is not engaged by the opening vane and is not moved into vertical alignment with the operating roller, the hoistway door remains locked and the operating roller, fixed to the lock hoistway door, remains immovable. The opening vane, engaging the immovable operating roller, therefore prevents the car door from horizontal opening movement. This event occurs only very rarely because the car usually aligns very closely with the hoistway door and the position at which the car door can be blocked occupies only an inch or so in the vertical extent of the hoistway at each floor. Nevertheless, despite the infrequency of the occurrence of this event, it remains a problem which until now had defied not only solution but identification.

The correction of this condition involves more problems than the mere design of a mechanism to prevent its occurrence. Since elevators of this basic design are in wide use throughout the industry, the economic aspects of modifying these many existing elevators must be carefully considered. The modification to correct the problem should be quickly and easily made by relatively unskilled mechanics. The modifying structure must be as simple and rugged as the structure it modifies to preserve the recognized advantages of the existing structure and preferably should itself be inexpensive to manufacture. The modifying structure should be adaptable to all elevators using the double-vane, double-roller operating mechanism, and finally, must absolutely assure opening of the elevator door irrespective of the position of the elevator car in the hoistway.

Accordingly, there is provided in accordance with the invention a means for preventing blockage of the car door due to engagement of the opening vane with the operating roller but not the unlocking roller. More particularly, there is provided an improved hoistway door operating clutch mechanism that assures opening of the car door at all positions in the hoistway irrespective of the relative position of the clutch vanes and hoistway door rollers.

The clutch mechanism of the invention includes a vertically extending leaf on the end of the opening clutch vane which will engage and unlock the unlocking roller when the vane engages the operating roller. The leaf is yieldably mounted on the end of the vane so that, if the vane itself is vertically misaligned with both operating and unlocking rollers, and the leaf is horizontally aligned with only the operating roller, it will yield to the operating roller, allowing the vane to pass and thereby permitting the elevator car door to open.

For a more complete understanding of the invention, reference may be had to the following detailed description taken in conjunction with the accompanying figures of the drawings, in which: i

FIG. 1 is a partial plan view looking toward the elevator door of a door operating clutch including a pair of clutch vanes bracketing a pair of rollers, and shows a preferred embodiment of the vane extension in accordance with the invention;

FIG. 2 is a cross-sectional view taken along the lines 2-2 of FIG. 1 and looking in the direction of the arrows;

FIG. 3 is a cross-sectional view taken along the lines 3-3 of FIG. 1 and looking in the direction of the arrows;

FIG. 4 is a diagrammatic sketch showing a prior art opening vane engaging the operating roller but not the unlocking roller with the result that the car door is blocked from opening;

FIG. 5 is a diagrammatic sketch showing an opening vane, equipped with a vane extension in accordance with the invention, engaging the operating roller while the vane extension engages and unlocks the unlocking roller;

FIG. 6 is a diagrammatic sketch showing the opening vane vertically misaligned with both rollers and the vane extension aligned with, but yielding to, the locked operating roller, permitting the car door to open;

FIG. 7 is a plan view of an alternative embodiment of the invention;

FIG. 8 is a partial cross-sectional view taken along the lines 8-8 in FIG. 7 and looking in the direction of the arrows; and

FIG. 9 is a cross-sectional view taken along the lines 9-9 in FIG. 7 and looking in the direction of the arrows.

Referring now to the drawings wherein like reference characters designate identical or corresponding parts, and more particularly to FIG. 1 thereof, the hoistway door operating mechanism includes an opening vane 12 having an operating face 13, and a closing vane 14 connected to a car door in parallel, vertically extending, horizontally spaced relationship. The opening vane 12 is directly connected to the car door 10 by means of flex plates 16 which permit the vane 12 to retract toward the car door 10 if necessary, in a manner analogous to that shown in U.S. Pat. No. 2,974,751, assigned to a common assignee. The closing vane 14 is connected to a structure which permits horizontal movement relative to the opening vane 12 for the purpose of gripping the roller structure between the vanes 12 and 14.

A roller structure 18 is fastened to the hoistway door 19 and includes an operating roller 20 and an unlocking roller 22. The unlocking roller 22 is journaled on the end of one arm 24 of a bell crank which itself is pivotally mounted on a pivot pin 25 connected to the hoistway door 19. The other arm 23 (shown broken off for clarity of illustration) of the bell crank operates a lock on the hoistway door 19 as will appear in more detail below. The operating roller 20 is journaled to the hoistway door 19 by means of the same pivot pin 25 on which the bell crank is pivotally mounted.

The operation of the structure described thus far is similar to that shown in U.S. Pat. No. 2,974,751, except an unlocking roller structure has been added. When the car door 10 is aligned with a hoistway entrance, the car door operating motor is energized and the car door 10 begins moving to the left as seen in FIG. 1. The operating face 13 of the opening vane 12 first engages the unlocking roller 22 and pushes it into vertical alignment with operating roller 20 thereby pivoting lever arm 24 counterclockwise about pivot pin 25. The other bell crank arm 23 (shown mostly broken off for clarity of illustration) pivots counterclockwise and effects unlocking of the hoistway door 19. Simultaneously, the

closing vane 14 moves horizontally toward the opening vane 12 to grip the aligned rollers 22 and 20 between the two vanes to prevent clatter or vibration of the hoistway door 19 as it opens. Continued leftward horizontal movement of the opening vane 12 moves the operating roller 20 and the hoistway door 19 to which it is attached toward the left, thereby opening the hoistway door 19 simultaneously with the car door 10.

The problem arises when the car door 10 is misaligned with the hoistway door 19 such that the opening vane 12 engages the operating roller 20 but not the unlocking roller 22, as illustrated in FIG. 4. When this condition occurs, the hoistway door 19 remains locked because the unlocking roller 22 has not been moved into vertical alignment with the operating roller 20 and the locking arm 23 of the bell crank remains in locked position. The hoistway door 19 therefore remains locked and the operating roller 20 to which it is attached remains immovable. The opening vane 12, engaging the immovable roller 20, is thus prevented from horizontal movement and the bar door 10 to which the opening vane 12 is attached is prevented from opening. To correct this condition it is necessary to restart the elevator car and move it a few inches to align the opening vane 12 with both the operating roller 20 and unlocking roller 22 as illustrated in FIG. 1, at which time the mechanism will function as intended.

To correct the problem illustrated in FIG. 4, the addition of a few inches to the upper end of opening vane 12 would suffice to cause the unlocking roller 22 to be moved into vertical alignment with the operating roller 20. This solution however merely shifts the problem zone a few inches. Misalignment of the car door merely a few inches lower would then present the same problem. What is needed is a vertical extension on the upper end of the opening vane 12 which will exert a horizontal force on the movable unlocking roller 22 but will yield to the resisting force of a locked operating roller 20 if aligned only therewith. In other words, if, as illustrated in FIG. 5, an extension 26 is added to the top of the opening vane 12 capable of exerting a horizontal force on the unlocking roller 22 sufficient to shift it into vertical alignment with the operating roller 20, then the hoistway door will be unlocked and engagement of the opening vane 12 with the operating roller 20 will permit the hoistway door and car door 10 to open. If, on the other hand, the opening vane 12 is misaligned with both rollers such that only the vane extension 26 is aligned with the operating roller 20, then horizontal movement of the opening vane 12 will'cause the vane extension 26 to engage the immovable operating roller 20, but since the vane extension 26 is yieldable to the resisting force of the locked, immovable operating roller 20, the vane extension 26 will pivot clockwise as shown in FIGS. 3 and 6 and permit the opening vane 12 to pass horizontally so that the car door 10 can open. Of course the hoistway door will remain closed and locked but it may be opened manuallyby the passengers or by the operating personnel. Most importantly, however, the car door 10 will not be blocked from opening at any point in the hoistway out will open freely even in the critical zone indicated.

Referring back to FIGS. 1 and 2, the vane extension 26 devised for exerting this horizontal force on the unlocking roller 22, but yielding to the resisting force of the immovable operating roller 20, is a leaf member 28 pivotably mounted on the end of the opening vane 12 by means of a pivot pin 30 connected to the inside face 31 of the opening vane 12 by means of a bracket 32 secured to the opening vane 12 by means of conventional fasteners such as screws 34. The leaf member 28 under the influence of a volute spring 36 of suitable selected characteristics is capable of exerting a horizontal force of a predetermined magnitude, but will yield to a horizontal force above a threshold magnitude. The volute spring 36 is coiled about the pivot pin 30 and bears at one end against the bracket 32 and the other end against the leaf member 28. The leaf member 28 is thus selectively displaceable, that is, will yield or be displaced by a force of predetermined or selected magnitude.

The leaf member 28 comprises a stop arm 38 and an operating arm 40 integrally connected at 42 forming an angle of approximately 80. Pivot pin 30 extends through a central aperture formed through each of two disks 44 connected to the top and bottom of the arms 38 and 40 respectively at the junction thereof to provide the journal about which leaf member 28 pivots. As best seen in FIG. 1, arm 38 acts as a stop to prevent volute spring from pivoting arm 40 beyond the plane of the operating face 13 of vane 12 so that the plane of the operating face of arm 40 coincides with the vertical plane of the operating face 13 of vane 12.

When the unlocking roller 22 is mounted above the operating roller 20, as illustrated, the vane extension 26 must be mounted on the top of the opening vane 12. This is so because the stated problem occurs only when the top end of the opening vane misses the unlocking roller 22 and engages only the operating roller alignment of the opening vane 12 with the pair of rollers 20 and 22 such that the bottom end of the opening vane 12 misses the operating roller 20 and engages only the unlocking roller 22 will permit the hoistway door to be unlocked and opened by horizontal force exerted by the opening vane 12 through the unlocking roller 22 to the hoistway door.

If, however, the unlocking roller 22 is mounted beneath the operating roller 20, then the vane extension 26 must be mounted on the bottom of the opening vane 12. This is because the problem occurs only when the bottom of the opening vane 12 misses the unlocking roller 22 and engages only the operating roller 20. Similarly, with that arrangement of rollers, alignment of the opening vane 12 with the rollers such that the top end of the opening vane 12 misses the operating'roller 20 and engages only the unlocking roller 22 will cause the hoistway door to be unlocked and opened as before.

The leaf member 28 is symmetrical and therefore may be mounted on the top or bottom of the opening vane irrespective of whether the opening vane 12 is on the right or left of the pair of rollers 20 and 22, and therefore is adapted to use in virtually any double-vane, double-roller mechanism.

The alternative embodiment of FIGS. 7, 8 and 9 in- 'cludes a modified form of vane extension 50 and, incidentally, a simplified form of closing vane operating structure 46. The modified vane extension 50 is formed of a single piece of spring steel having an operating leaf 52 and an integrally formed orthogonally disposed anchoring leaf 54. The operating leaf 52 is of virtually the same shape as the operating arm 40 of the species disclosed in FIGS. l-6, that is, in the form of a downwardly sloping parallelogram.

The operating leaf 52 is connected at its upper verti cal edge to the anchoring leaf 54. The anchoring leaf 54 has a downwardly sloping top surface 56 and a rectangular depending section 58 through which is formed a pair of vertically spaced holes which receive a pair of screws 60 by which the structure is fastened to the rear face of the opening vane 13.

In use, the spring form of the opening vane extension operates in substantially the same selectively displaceable manner as the species illustrated in FIGS. L6. instead of pivoting against the force of the volute spring 36, however, the species illustrated in FIGS. 7-9 flexes principally at the junction of operating leaf 52 and anchoring leaf 54. The spring characteristics are selected to enable sufficient force to he exerted on the unlocking roller to shift it into vertical alignment with the operating roller, and yet sufficiently pliable to flex and allow the car door to open when the operating roller is locked.

Thus there is provided in accordance with the invention a selectively displaceable extension for attachment to an opening vane of a hoistway door operating clutch mechanism that will exert sufficient force to unlock an unlocking roller if aligned therewith, but will yield to a locked operating roller if aligned therewith, thereby positively precluding blockage of the car door by a locked operating roller.

It will be understood by those skilled in the art that the above described embodiments are meant to be merely exemplary, and that they are susceptible of modification and change without departing from the spirit and scope of the invention. For example, the vane extensions 26 and 50 could comprise a single leaf arm with a simple peg attached thereto for use with an angle iron opening vane. The leaf could be pivoted for pivotal movement about a vertical or horizontal axis and indeed could comprise a simple leaf spring rigidly attached to the angle iron opening vane and flexing about an horizontal axis. Other more complicated mechanisms are contemplated such as a pair of triangular prisms vertically aligned with their apexes abutting and their bases horizontal. They would be spring biased toward each other and would separate-vertically away from each other against their biasing springs when they encountered a locked operating roller. Therefore, the invention is not deemed to be limited except as defined by the appended claims.

I claim:

1. In an elevator system having a car vertically movable in a hoistway and having a horizontally movable door selectively alignable with respective ones of a plurality of vertically spaced horizontally movable hoistway doors, each carrying an operating roller for opening the hoistway door and a vertically spaced unlocking roller horizontally movable for unlocking the hoistway door, the car door carrying a pair of vertically extending horizontally spaced clutch vanes, one of which is an opening vane having a vertically extending operating face engageable with the operating roller, wherein the opening vane on the opening elevator car door first engages the unlocking roller and moves it to unlocking position, and then engages the operating roller to effect horizontal opening movement of the hoistway door, the improvement comprising: selectively displaceable extension means for adding an increment to the vertical dimension of the opening vane at one vertical extremity thereof and for exerting a horizontal force in said vertical increment ofa predetermined magnitude, but yielding to a resisting horizontal force above said predetermined magnitude, whereby when the opening vane is aligned only with the operating roller and misaligned with the unlocking roller, the unlocking roller will be moved by said extension means to unlock the hoistway door; when the opening vane is misaligned with both the operating roller and the unlocking roller and the extension means is aligned with the operating roller, the extension means will yield and allow the opening vane to pass and allow the elevator car door to open.

2. The improved elevator door clutch as defined in claim 1, wherein said selectively displaceable extension means comprises a vertically extending leaf yieldably mounted on the opening vane and presenting a vertically extending face for exerting said predetermined force on objects in a horizontal zone extending above the horizontal path of the opening vane but yielding to immovable objects in said horizontal path to permit the opening vane to pass.

3. The improved elevator door clutch as defined in claim 2, further comprising means for pivotally mounting said leaf on a vertical extremity of the opening vane for pivotal movement thereon; and biasing means for biasing said leaf into the vertical plane of the opening vane operating face and against said pivotal movement.

4. The improved elevator door clutch as defined in claim 3, wherein said mounting means includes a vertical pivot pin connected to the opening vane; and said biasing means includes a volute spring disposed coaxially around said pivot pin and having the ends thereof bearing against said leaf and the vane respectively.

5. The improved elevator door clutch as defined in claim 3, wherein said leaf comprises a pair of leaf arms, one of said arms comprising said face, and the other of said arms bearing against a member fixed with respect to said vane to prevent said leaf from pivoting beyond said plane under the influence of said biasing means.

6. The improved elevator door clutch as defined in claim 5, wherein said mounting means includes a vertical pivot pin connected to said opening vane; and said biasing means includes a volute spring disposed coaxiallyaround said pivot pin and having the ends thereof bearing against said leaf and the vane respectively.

7. The improved elevator door clutch as defined in claim 2, wherein said vertically extending leaf comprises an integrally formed spring steel structure which itself exerts said horizontal force when moved by the car door into engagement with the unlocking roller, and which itself flexes and permits the car door to open when aligned with a locked operating roller.

8. The improved elevator door clutch as defined in claim 7, wherein said integrally formed spring steel structure includes an operating leaf and an angularly disposed integrally formed anchoring leaf attachable to the opening vane.

9. The improved elevator door clutch as defined in claim 8, wherein said operating leaf and said anchoring leaf both are generally vertically oriented and the connection therebetween is substantially only along their respectively adjacent edges, 

1. In an elevator system having a car vertically movable in a hoistway and having a horizontally movable door selectively alignable with respective ones of a plurality of vertically spaced horizontally movable hoistway doors, each carrying an operating roller for opening the hoistway door and a vertically spaced unlocking roller horizontally movable for unlocking the hoistway door, the car door carrying a pair of vertically extending horizontally spaced clutch vanes, one of which is an opening vane having a vertically extending operating face engageable with the operating roller, wherein the opening vane on the opening elevator car door first engages the unlocking roller and moves it to unlocking position, and then engages the operating roller to effect horizontal opening movement of the hoistway door, the improvement comprising: selectively displaceable extension means for adding an increment to the vertical dimension of the opening vane at one vertical extremity thereof and for exerting a horizontal force in said vertical increment of a predetermined magnitude, but yielding to a resisting horizontal force above said predetermined magnitude, whereby when the opening vane is aligned only with the operating roller and misaligned with the unlocking roller, the unlocking roller will be moved by said extension means to unlock the hoistway door; when the opening vane is misaligned with both the operating roller and the unlocking roller and the extension means is aligned with the operating roller, the extension means will yield and allow the opening vane to pass and allow the elevator car door to open.
 2. The improved elevator door clutch as defined in claim 1, wherein said selectively displaceable extension means comprises a vertically extending leaf yieldably mounted on the opening vane and presenting a vertically extending face for exerting said predetermined force on objects in a horizontal zone extending above the horizontal path of the opening vane but yielding to immovable objects in said horizontal path to permit the opening vane to pass.
 3. The improved elevator door clutch as defined in claim 2, further comprising means for pivotally mounting said leaf on a vertical extremity of the opening vane for pivotal movement thereon; and biasing means for biasing said leaf into the vertical plane of the opening vane operating face and against said pivotal movement.
 4. The improved elevator door clutch as defined in claim 3, wherein said mounting means includes a vertical pivot pin connected to the opening vane; and said biasing means includes a volute spring disposed coaxially around said pivot pin and having the ends thereof bearing against said leaf and the vane respectively.
 5. The improved elevator door clutch as defined in claim 3, wherein said leaf comprises a pair of leaf arms, one of said arms comprising said face, and the other of said arms bearing against a member fixed with respect to said vane to prevent said leaf from pivoting beyond said plane under the influence of said biasing means.
 6. The improved elevator door clutch as defined in claim 5, wherein said mounting means includes a vertical pivot pin connected to said opening vane; and said biasing means includes a volute spring disposed coaxially around said pivot pin and hAving the ends thereof bearing against said leaf and the vane respectively.
 7. The improved elevator door clutch as defined in claim 2, wherein said vertically extending leaf comprises an integrally formed spring steel structure which itself exerts said horizontal force when moved by the car door into engagement with the unlocking roller, and which itself flexes and permits the car door to open when aligned with a locked operating roller.
 8. The improved elevator door clutch as defined in claim 7, wherein said integrally formed spring steel structure includes an operating leaf and an angularly disposed integrally formed anchoring leaf attachable to the opening vane.
 9. The improved elevator door clutch as defined in claim 8, wherein said operating leaf and said anchoring leaf both are generally vertically oriented and the connection therebetween is substantially only along their respectively adjacent edges. 